Strontium titanate structure

Figure 4 Raman spectra of a series of strontium titanates showing typicai iine shapes and information avaiiabie for fingerprinting. The broadening of the high-wavenumber lines is related to the polar character of the TiOs octahadra that occur in all of these structures.

Domen, K., Kudo, A., Onishi, T., Kosugi, N., and Kuroda, H., Photocatalytic decomposition of water into hydrogen and oxygen over nickel (II) oxide-strontium titanate (SrTiOj) powder. 1. Structure of the catalysts, ]. Phys. Chem., 90, 292,1986. 

Alkaline-Earth Titanates. Some physical properties of representative alkaline-earth titanates are listed in Table 15. The most important applications of these titanates are in the manufacture of electronic components (109). The most important member of the class is barium titanate, BaTi03, which owes its significance to its exceptionally high dielectric constant and its piezoelectric and ferroelectric properties. Further, because barium titanate easily forms solid solutions with strontium titanate, lead titanate, zirconium oxide, and tin oxide, the electrical properties can be modified within wide limits. Barium titanate may be made by, eg, cocalcination of barium carbonate and titanium dioxide at ca 1200°C. With the exception of Ba iO barium orthotitanate, titanates do not contain discrete TiO4 ions but are mixed oxides. Ba2Ti04 has the p-I SC structure in which distorted tetrahedral TiO4 ions occur. 

Slonczewski JC, Thomas H (1970) Interaction of elastic strain with the structural transition of strontium titanate. Phys Rev B 1 3599-3608... 

Figure 1 shows the two models which were calculated. The base structure was considered with another research group for improvement of the thermal conductivity, while three layered structure was adopted on the view point of shielding. The base structure was assumed to be a concentric cylinder of 60 cm height which was formed void, strontium titanate ( "SrTiOs, P 5.12g/cm 0 and boron nitride (BN, p 2.26g/cm3) from the inside. The weight of these two materials was made to be identical each other. 

In this chapter, the commonly held belief that the terms ceramic and brittle are synonymous has been shown not to be exactly tenable. Oxide single crystals with the rock-salt structure can be deformed plastically at liquid helium temperatures, while strontium titanate shows an inverse BDT and can be deformed plastically at ambient temperatures and below. Oxides with the fluorite structure can be deformed... 

De Souza RA, Fleig J, Maier J, Kienzle O, Zhang Z, Sigle W, Riihle M (2003) Electrical and structural characterization of a low-angle tilt grain boundary in iron-doped strontium titanate. J Am Ceram Soc 86 922-928... 

Crystalline strontium titanate has no pore structure and its effectiveness as a vanadium trap is reliant vpoi maximizing its external surface area. This is achieved by reducing the average particle size of the tr, by milling and classlflcaticxi, to levels ccnparable with other catalyst ingredients. 

Since 2009, several papers have been published which consider the bond valence of surfaces. Many have involved the L. Marks and Poeppelmeier groups at Northwestern University and deal with the surfaces of strontium titanate (SrTiOa). These include a discovery of a homologous series of surface structures on SrTiOs (110) [6], studies of the (2 x 2) [10], c(4 x 2) [11], and (Vl3 x Vl3)/ 33.7° [12] surface reconstructions on the SrTiOs (100) surface, an examination of water adsorbed on the SrTiOs (100) surface [13, 14], and a review of several previously proposed surface structures on SrTiOs, MgO, and NiO from a bond valence perspective [15]. 

Deak DS (2007) Strontium titanate surfaces. Mater Sci Technol 23(2) 127-136 Noguera C (2000) Polar oxide surfaces. J Phys Condens Matter 12(31) R367-R410 Enterkin JA, Suhramanian AK, Russell BC, Castell MR, Poeppelmeier KR, Marks LD (2010) A homologous series of structures on the surface of SrTiOa (110). Nat Mater 9(3) 245-248 Brown ID (2009) Recent developments in the methods and applications of the bond valence model. Chem Rev 109(12) 6858-6919... 

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